1. Technical Field
The present invention relates to a hybrid vehicle and control method of the hybrid vehicle.
2. Description of the Prior Art
One known structure of the hybrid vehicle includes an engine, a planetary gear unit linked with a first motor and with an axle, a second motor connected to the axle, and a battery transmitting electric power to and from the first and the second motors and enables the engine to be driven at any arbitrary drive point irrespective of the setting of a gearshift position SP (see Japanese Patent Laid-Open No. 2006-321458). The available gearshift positions settable by the driver's operation of a gearshift lever in the hybrid vehicle include a sequential gearshift position, an upshift instruction position, and a downshift instruction position, in addition to the conventional gearshift positions including a drive position. In response to the driver's operation of the gearshift lever to select either the upshift instruction position or the downshift instruction position after selection of the sequential gearshift position, the speed ratio of the engine rotation speed to the vehicle speed is changeable at multiple different stages. Another proposed structure of the hybrid vehicle refers to a minimum engine speed map in response to the driver's depression of an accelerator pedal in selection of a sports drive mode to specify a minimum engine speed corresponding to the vehicle speed and controls the engine to keep the engine rotation speed higher than the specified minimum engine speed (see Japanese Patent Laid-Open no. 2005-124282). In the hybrid vehicle of this configuration, the engine rotation speed is kept at or above the specified minimum engine speed in the sports drive mode. This expands a variable torque range by the engine and ensures a quick increase or decrease in torque output from the engine.